Biology subjects

Pedro F Vale

Publications and source records attributed to Pedro F Vale.

3 recordsLinked to original sources

bioRxiv2016

Wolbachia confers sex-specific resistance and tolerance to enteric but not systemic bacterial infection in Drosophila

Wolbachia-mediatedprotection against viral infection has been extensively demonstrated in Drosophila and in mosquitoes that are artificially inoculatedwith D. melanogaster Wolbachia (wMel), but to date no evidence for Wolbachia-mediated antibacterial protection has been demonstrated in Drosophila.Here we show that D. melanogaster carrying wMel shows reduced mortality during enteric - but not systemic - infection with the opportunist pathogen Pseudomonas aeruginosa, and that protection is more pronounced in male flies. Wolbachia-mediated protection is associated with increased early expression of the antimicrobial peptide attacinA, followed by increased expression of a ROS detoxification gene (gstD8), and other tissue damage repair genes which together contribute to greater host resistance and disease tolerance. These results highlight that the route of infection is important for symbiont-mediated protection from infection, that Wolbachia can protect hosts by eliciting a combination of resistance and disease tolerance mechanisms, and that these effects are sexually dimorphic.

Microbiology↗

bioRxiv2016

Infection avoidance behaviour: female fruit flies adjust foraging effort in response to internal and external cues of viral infection

Infection avoidance behaviours are the first line of defence against pathogenic encounters. Behavioural plasticity in response to internal or external cues can therefore generate potentially significant heterogeneity in infection. We tested whether Drosophila melanogaster exhibits infection avoidance behaviour during foraging, and whether this behaviour is modified by prior exposure to Drosophila C Virus (DCV) and by the risk of DCV encounter. We examined two measures of infection avoidance: (1) the motivation to feed in the presence of an infection risk and (2) the preference to feed on a clean food source over a potentially infectious source. While we found no clear evidence for preference of clean food sources over potentially infectious ones, female flies were less motivated to feed when presented with a risk of encountering DCV, but only if they had been previously exposed to the virus. We discuss the relevance of behavioural plasticity during foraging for host fitness and pathogen spread.

Animal Behavior and Cognition↗

bioRxiv2015

Microbiome engineering could select for more virulent pathogens

Recent insights into the human microbiome offer the hope of manipulating its composition to help fight infectious diseases1-7. While this strategy has shown huge potential, its consequences for pathogen evolution have not been explored. Here we show that manipulating the microbiome to increase the competition that pathogens face could lead to the evolution of increased production of virulence factors that pathogens use to combat commensals, an evolutionary response that can increase total disease induced mortality in the long-term. However, if treatment with microbiome engineering is sufficiently aggressive this evolutionary response can be avoided and the pathogen eradicated. Furthermore, we show that using damage limitation therapies8 (e.g. antivirulence and anti-inflammatory drugs) in combination with microbiome manipulation increases the potential for pathogen eradication. While manipulating our microbiota offers a promising alternative to antibiotics, our results show that these treatments must be designed with careful consideration of the potential evolutionary responses of target pathogens.

Microbiology↗